'92 F-150 302 EFI w/ Powerdyne 6 lb boost set-up.

I know that you get the most power/ boost out of a centrifugal blower at 3000 - 5000 RPM. I NEVER run the revs up past 3300.

Does it make any sense to reduce the SC pulley size to increase boost at lower RPM? Or will this just drag the engine?

Powerdyne warned me about doing this b/c of precombustion, but if i don't run the engine all the way up, i shouldn't have to worry about that, right?

 

Putting a smaller pulley on the supercharger...or larger crank pulley if it's a separate setup will help you make boost at lower rpms. I just don't know about pullying up a Powerdyne is a good thing. That internal belt setup doesn't seem to like boost increases.

Look into an intercooler kit if detonation is a big concern.

 

If this is a BD-11, then I wouldn't spin that thing past 8psi...they're not very efficient compressors beyond that.

Powerstroke diesel intercoolers can be picked up for around $200 off of ebay. I installed one in my 94 Lightning and it works great. Ya just need to get someone to fab up the ductwork and you're set!

 

It wouldn't really be a boost increase, i never get more than 2-3 psi out of it(according to my gauge), but then again, ever since i sent my water pump and fan through the radiator i have been a little hesitant to rev the engine up really high (solved that little problem though, only took 4 water pumps, 1 radiator, and one cold day in Indiana). The spacer Powerdyne provided for the fan off of the water pump wasn't very good.

I would like to get the rated boost (6 psi) at around 3800 RPM. Is it possible that this would make my engine perform worse?

It is a BD-11.

 

First of all, what other mods do you have done to your truck? Are you running an FMU, boost retard, an inline pump etc...???
You don't want to go and spin your blower faster if you don't have the fuel and ignition system to support it. We'll need some details.

 

Other than the FMU that came with the Powerdyne kit, everything with the fuel system/ engine is stock (fuel pump, coil, cap, rotor, wires, plugs, etc.)

I have been thinking about up-grading some of these components and i know it opens a whole bag of worms.

What do you recommend?

 

I would strongly recommend you getting an inline fuel pump and some type of boost retard to keep it from detonating. When you force more air into your motor you need to give it more fuel to keep it from leaning out. Powerdyne has a 200lph inline that comes with a check valve (i'm suprised that you didn't get this pump with your SC'er kit) to allow fuel to pass around it when it's not running. Walboro makes a 255lph inline that is excellent, but that'll probably be more than you need if you don't plan on getting crazy with the boost down the road.
How are you tuning your combo?

 

Everything is still stock from the ignition, coil, distributor, wires, plugs, timing, computer to the exhaust.
I'm looking for a compromise between power and fuel efficiency (starting to cost an arm and a leg to operate my truck, and i have a few long interstate drives coming up).

for the fuel pump, i have high pressure pumps in my tanks, will the in-line work with these? or do i need to replace the in-tank pumps?

So what do you think, start w/ a fuel pump up-grade and go to an MSD ignition system, coil and distributor? Or another manufacturer?

Thanks for the input!

IW

 

What size pumps are in the tanks?
You may or may not need an inline pump; however, you really need to check your A/F ratios and fuel pressure under boost to be sure. Something to keep in mind is installing an inline pump (wether you need it or not) gives you a little added insurance. The pump operates off of a relay and pressure (Hobbs) switch, and activates under boost to increase the fuel pressure.
Be sure the ignition system you purchase and install is equipped with a boost retard. I wouldn't worry about replacing the coil unless it's bad, and just make sure the rest of your ignition system is in good working order. You'll need to pull a little timing when you increase the boost. I was able to set mine to pull 0.8* per 1 psi of boost with the combo I ran last year, on 93 octance.
ALSO, it's a good idea to run a set of spark plugs that are one heat range colder than stock, this will help to keep the combustion temp in check.

 

did you notice an increase in power with your intercooler

 

The charge temps were much lower, with the PSD intercooler, and I was able to run more timing because of it.